
PASS addTrack when pc is closed should throw InvalidStateError 
PASS addTrack with single track argument and no stream should succeed 
PASS addTrack with single track argument and single stream should succeed 
PASS addTrack with single track argument and multiple streams should succeed 
PASS Adding the same track multiple times should throw InvalidAccessError 
PASS addTrack with existing sender with null track, same kind, and recvonly direction should reuse sender 
PASS addTrack with existing sender that has not been used to send should reuse the sender 
PASS addTrack with existing sender that has been used to send should create new sender 
PASS addTrack with existing sender with null track, different kind, and recvonly direction should create new sender